Section 4A. It shall be an unfair labor practice for any person or labor organization—

(1) To seize or occupy unlawfully private property as a means of forcing settlement of a labor dispute; or

(2) To authorize or engage in any strike, slowdown, boycott or other concerted cessation of work or withholding of patronage for the purpose of—

(a) Bringing about, directly or indirectly, the commission of any unfair labor practice, or

(b) Injuring or interfering with the trade or business of any person because such person has refused to commit an unfair labor practice; or

(c) Interfering with, restraining or coercing employees in their choice or rejection of representatives for the purpose of collective bargaining after the commission has determined in a proceeding under section five that such employees do not desire to be represented by such labor organization; or

(3) To aid in any concerted activities of the types described in this section by giving direction or guidance in the conduct thereof or by providing funds for the payment of strike, unemployment or other benefits to persons participating therein; or

(4) To interfere with, restrain or coerce an employer or employee in the exercise of a right guaranteed under this chapter.